521 research outputs found

    Elective Modernism and the Politics of (Bio) Ethical Expertise

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    In this essay I consider whether the political perspective of third wave science studies – ‘elective modernism’ – offers a suitable framework for understanding the policy-making contributions that (bio)ethical experts might make. The question arises as a consequence of the fact that I have taken inspiration from the third wave in order to develop an account of (bio)ethical expertise. I offer a prĂ©cis of this work and a brief summary of elective modernism before considering their relation. The view I set out suggests that elective modernism is a political philosophy and that although its use in relation to the use of scientific expertise in political and policy-making process has implications for the role of (bio)ethical expertise it does not, in the final analysis, provide an account that is appropriate for this latter form of specialist expertise. Nevertheless, it is an informative perspective, and one that can help us make sense of the political uses of (bio)ethical expertise

    Crack-Like Processes Governing the Onset of Frictional Slip

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    We perform real-time measurements of the net contact area between two blocks of like material at the onset of frictional slip. We show that the process of interface detachment, which immediately precedes the inception of frictional sliding, is governed by three different types of detachment fronts. These crack-like detachment fronts differ by both their propagation velocities and by the amount of net contact surface reduction caused by their passage. The most rapid fronts propagate at intersonic velocities but generate a negligible reduction in contact area across the interface. Sub-Rayleigh fronts are crack-like modes which propagate at velocities up to the Rayleigh wave speed, VR, and give rise to an approximate 10% reduction in net contact area. The most efficient contact area reduction (~20%) is precipitated by the passage of slow detachment fronts. These fronts propagate at anomalously slow velocities, which are over an order of magnitude lower than VR yet orders of magnitude higher than other characteristic velocity scales such as either slip or loading velocities. Slow fronts are generated, in conjunction with intersonic fronts, by the sudden arrest of sub-Rayleigh fronts. No overall sliding of the interface occurs until either of the slower two fronts traverses the entire interface, and motion at the leading edge of the interface is initiated. Slip at the trailing edge of the interface accompanies the motion of both the slow and sub-Rayleigh fronts. We might expect these modes to be important in both fault nucleation and earthquake dynamics.Comment: 19 page, 5 figures, to appear in International Journal of Fractur

    Who are these youths? Language in the service of policy

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    In the 1990s policy relating to children and young people who offend developed as a result of the interplay of political imperatives and populist demands. The ‘responsibilisation’ of young offenders and the ‘no excuses’ culture of youth justice have been ‘marketed’ through a discourse which evidences linguistic changes. This article focuses on one particular area of policy change, that relating to the prosecutorial decision, to show how particular images of children were both reflected and constructed through a changing selection of words to describe the non-adult suspect and offender. In such minutiae of discourse can be found not only the signifiers of public attitudinal and policy change but also the means by which undesirable policy developments can be challenged

    Dissipation of vibration in rough contact

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    The relationship which links the normal vibration occurring during the sliding of rough surfaces and the nominal contact area is investigated. Two regimes are found. In the first one, the vibrational level does not depend on the contact area, while in the second one, it is propor- tional to the contact area. A theoretical model is proposed. It is based on the assumption that the vibrational level results from a competition between two processes of vibration damping, the internal damping of the material and the contact damping occurring at the interface

    Multiscale friction in lubricant-surface systems for high performance transmissions under mild wear

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    The lubricant-surface system is complex in nature and can significantly affect the frictional performance of high-performance transmission systems. The complexity stems from the coupled mechanical and chemical phenomena that occur at the interfacial tooth conjunctions. A combined analytical and precision experimental approach is presented to analyse the salient parameters of the lubricant-surface system. A multiscale procedure comprising topographical measurement, pin-on-disc tribometry, atomic force microscopy in lateral force mode, X-ray photo-electron spectroscopy and continuum contact mechanics analysis under mixed non-Newtonian thermo-elastohydrodynamics is used to describe the formation of a tribo-film, as well as wear and frictional characteristics of the lubricant-surface system. The contribution of chemisorbed and physisorbed bonded tribo-film on the boundary coefficient of friction is ascertained at different physical scales. Therefore, the paper presents a novel multiscale analysis, promoting improved understanding of the complex interactions between mechanisms of friction, wear and surface chemistry

    On the nature of surface roughness with application to contact mechanics, sealing, rubber friction and adhesion

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    Surface roughness has a huge impact on many important phenomena. The most important property of rough surfaces is the surface roughness power spectrum C(q). We present surface roughness power spectra of many surfaces of practical importance, obtained from the surface height profile measured using optical methods and the Atomic Force Microscope. We show how the power spectrum determines the contact area between two solids. We also present applications to sealing, rubber friction and adhesion for rough surfaces, where the power spectrum enters as an important input.Comment: Topical review; 82 pages, 61 figures; Format: Latex (iopart). Some figures are in Postscript Level

    Citizenship Education and the Role of Immigrant Students in the Nordic Countries

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    This chapter addresses the issue of citizenship education and the role of immigrant students in the Nordic countries from the perspective of liberal theories of citizenship education. Liberal approaches to citizenship education have recently encountered rigorous critique: the critics argue that the supposedly democratic, rational, and neutral principles and ideals associated with liberal theories are in reality rooted in a particular way of life and national identity. Accordingly, inculcating these principles and ideals in citizenship education excludes and marginalizes students belonging to minorities, immigrant students in particular. This chapter aims to respond to this critique by separating between two branches of liberal theories of citizenship education, ‘patriotic’ and ‘political’. The chapter argues that while the ‘patriotic’ approach is vulnerable to the aforementioned critique, it does not apply to the ‘political’ line of thought. Rather, the ‘political’ approach, rooted in John Rawls’ political liberalism and the notion of reasonableness, provides a foundation for criticizing policies and practices that marginalize students with immigrant backgrounds. Finally, utilizing Rawlsian theory of citizenship education as a starting point, the chapter makes some suggestions on how the status of immigrant students could be improved in the Nordic countries.Peer reviewe

    Computational Modelling of Patella Femoral Kinematics During Gait Cycle and Experimental Validation

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    The effect of loading and boundary conditions on patellar mechanics is significant due to the complications arising in patella femoral joints during total knee replacements. To understand the patellar mechanics with respect to loading and motion, a computational model representing the patella femoral joint was developed and validated against experimental results. The computational model was created in IDEAS NX and simulated in MSC ADAMS/VIEW software. The results obtained in the form of internal external rotations and anterior posterior displacements for a new and experimentally simulated specimen for patella femoral joint under standard gait condition were compared with experimental measurements performed on the Leeds ProSim knee simulator. A good overall agreement between the computational prediction and the experimental data was obtained for patella femoral kinematics. Good agreement between the model and the past studies was observed when the ligament load was removed and the medial lateral displacement was constrained. The model is sensitive to ±5 % change in kinematics, frictional, force and stiffness coefficients and insensitive to time step

    Making drug harms: Punishments for drugs offenders who pose risks to children

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    Images of children are routinely used in discourses on drugs, offering a compelling rationale for adopting particular policy positions or legislative reforms. However, the importance of childhood to the constitution of drug harms, and the punishment and subjectification of drug users and offenders, have rarely been the subject of enquiry, whether within drug and alcohol studies, criminology or legal studies. Scholarship on criminal sentencing in England and Wales is also relatively sparse, and has been dominated by analyses of the ‘legal-rational’ logic of particular provisions or reforms. This paper, which relies on the premise that drugs and their effects are constituted through discourse, and are thus contingent, variable and unstable, identifies the ‘collateral realities’ (Law, 2011) that are enacted during legislative and judicial attempts to stabilize the harms caused by drugs to children and communities
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